Sonic method and apparatus for installing pile member, casing members or the like, in earthen formations



April 23, 1968 BODINE, JR 3,379,263

SONIC METHOD AND APPARATUS FOR INSTALLING FILE MEMBER, CASING MEMBERS ORTHE LIKE, IN EARTHEN FORMATIONS 4 Sheets-Sheet 1 Filed Feb. 1, 1966 wm/TOP. M5527 500l/V6, J2.

A TTOE/VEY Aprll 23, 1968 A. 5. Booms. JR 3,379,263

SONIC METHOD AND APPARATUS FOR INSTALLING FILE MEMBER, CASING MEMBERS ORTHE LIKE, IN EARTHEN FORMATIONS Filed Feb. 1, 1966 4 Sheets-Sheet 2 lM'N Toe. ALBERT 6. BOD/NE, JE.

5y wme/m' flrromvey P" 1968 A. G. BODINE, JR 7 3 SONIC METHOD ANDAPPARATUS FOR INSTALLING FILE MEMBER, CASING MEMBERS OR THE LIKE, INEARTHEN FORMATIONS Filed Feb. 1, 1966 4 Sheets-Sheet 5 m l M/VA/TOR.

flLBf/PT e. Boo/NE, JE.

Apnl 23, 1968 500mg, JR 3,379,263

SOEJZC METHOD AND APPARATUS FOR INSTALLING FILE MEMBER, CASING MEMBERSOR THE LIKE, '[N EARTHEN FORMATIONS Flled Feb 1, 1966 4 Sheets-Sheet 4l/VVEN TOR.

I n Y Rm 2 B wJw D .T a 6 United States Patent 3,379,263 SONIC METHODAND APPARATUS FOR INSTAL- LING PILE MEMBER, CASING MEMBERS OR THE LIKE,IN EARTHEN FORMATIGNS Albert G. Bodine, Jr., 7877 Woodley Ave, Van Nuys,Calif. 91406 Continuation-impart of application Ser. No. 340,745, Jan.28, 1964. This application Feb. 1, 1966, Ser. No. 524,059

Claims. (Cl. 175-19) This application is a continuation-in-part of myapplication Ser. No. 340,745, filed Jan. 28, 1964, now Patent No.3,239,005 for Method for Molding Well Liners or the Like.

This invention relates to a method and apparatus for installing pilemembers, casing members or the like, in earthen formations, and moreparticularly to such a method and apparatus involving a first operationin which a hole for receiving such member is punched by means of asonically excited mandrel and a second operation in which the member tobe installed is sonically lodged in the pre-punched hole.

In the aforementioned patent application, of which the instantapplication is a continuation in part, a method is described wherein amandrel is sonically driven into the ground by virtue of resonantvibration thereof and then used as a mold for forming a casing by a slipform process. In this slip form process, sonic energy is coupled fromthe mandrel through the setting slurry to the surrounding soil. The soilis fluidized and compacted by sonic energy so as to tightly grip themolded casing member, thus assuring tight lodgement thereof in theground. The method and device of this invention provide an adaption andimprovement in this technique whereby prefabricated pile members, casingmembers or the like can be installed in earthen formations.

As described, for example, in my Patent No. 2,975,846, sonic energy canbe utilized to efiiciently drive a casing or pile member into an earthenformation. While such techniques of the prior art utilizing resonantvibrating systems in achieving sonic driving action are capable ofhighly efiicient operation, certain dilficulties are sometimesexperienced where the members to be driven have any modicum offrangibility, this in view of the fairly high level of sonic energy towhich such members may have to be subjected in achieving the necessarydriving action.

It is highly desirable that the driven pile or casing member be firmlylodged in the earthen formation in its final position, especially wheresuch member tends to be frangible. This is in view of the fact that withsuch firm retention of the casing or pile member, structuralreinforcement is provided therefor by the earthen formation. This notonly makes for greater structural stability but also provides greatereffective durability and load and tension bearing capabilities in thecasing or piling.

The method and apparatus of this invention overcomes the aforementioneddifiiculties by means of a twostep sonic activation of the earthenformation in which the casing or pile member is finally lodged. In thefirst of these steps, a mandrel member is sonically driven into theearthen formation to achieve two end results: (1) to prebore the groundand (2) to compact and effectively condition the earthen material sothat it is ideally prepared for a subsequent second fluidization andfinal compaction. After the pre-bore has been formed, the mandrel isremoved and the casing or pile member forced into the hole formed by themandrel by sonic excitation of such casing or pile member.

It is to be noted that with the method and apparatus of this invention,that the soil itself is not made part of the resonantly vibrating systemso that it does not form 3,379,263 Patented Apr. 23, 1958 a reactivecomponent of such system and therefore does not behave as a coherentvibrating mass. Rather, the earthen particles assume a random vibrationrelative to each other, resulting in a high degree of fiuidization andeventual compaction thereof. The vibration of the mandrel thus fiuidizesthe earthen material surrounding the bore and sets it up in a randompattern. The second energization of such particles with the excitationof the casing or pile member causes further fluidization and compactionand when the sonic energy is finally removed from the casing or pilemember when it arrives at its final position, the earthen particlessettle closely against the wall of such member to provide a tightgripping action along the entire length thereof. The two-step sonicprocess thus enables relatively easy installment of the casing or pilemember in an earthen formation and firm lodgement therein.

Apparatus is provided in one embodiment of the de vice of the inventionfor enabling a resonant system of relatively compact proportions whereinthe earth penetrating member provides a lumped constant load connectedto such system. In this type of system, the generation of high amplitudestanding waves in the casing or pile member is avoided, this membereffectively acting as a transformer to couple such energy to the soil.

It is therefore an object of this invention to provide an improved sonicmethod and apparatus for installing a casing or pile member in anearthen formation.

It is another object of this invention to minimize the hazard of damageto a relatively frangible casing or pile member in the installationthereof in an earthen formation.

It is still another object of this invention to provide a method andapparatus which makes for easier installation of casing or pile membersin an earthen formation.

It is still a further object of this invention to enable betterlodgement of easing or pile members in their installation in earthenformations.

It is still another object of this invention to improve the effectivedurability and weight and tension bearing characteristics of a givencasing or pile member in its earth-installed position.

It is still a further object of this invention to provide a resonantsonic driving system of more compact configuration.

Other objects of this invention will become apparent from the followingdescription taken in connection with the accompanying drawings, ofwhich:

FIG. 1 is an elevation view partly in cross-section illustrating a firstembodiment of the device of the invention operating to perform the firststep of the method of the invention,

FIG. 2 is a cross sectional View taken along the plane indicated by 22in FIG. 1,

FIG. 3 is a cross sectional view taken along the plane indicated by 33in FIG. 1,

FIG. 4 is a cross sectional view taken along the plane indicated by 44in FIG. 3,

FIG. 5 is an elevation view partly in cross section illustrating asecond embodiment of the device of the invention operating to performthe second step of the method of the invention,

FIG. 6 is a cross sectional view taken along the plane indicated by 6-6in FIG. 5,

FIG. 7 is a cross sectional view taken along the plane indicated by 7-7in FIG. 6, and

FIG. 8 is a view taken along the plane indicated by 88 in FIG. 7.

It has been found most helpful in analyzing the operation of the deviceof the invention to analogize the acoustically vibrating circuitinvolved to an equivalent electrical circuit.

This sort of approach to analysis is well known to those skilled in theart and is described, for example, in chapter 2 of Sonics by Hueter andBolt, published in 1955 by John Wiley and Sons. In making such ananalogy, force, F, is equated with electrical voltage, E; velocity ofvibration, u, is equated with electrical current, i; mechanicalcompliance, C is equated with electrical capacitance, C mass, M, isequated with electrical inductance, L; mechanical resistance (friction),R is equated with electrical resistance, R; and mechanical impedance, Zis equated with electrical impedance, Z

Thus, it can be shown that if a member is elastically vibrated by meansof an acoustical sinusoidal force, F sin out, (to being equal to 21rtimes the frequency of vibration), that Where wm is equal to l/wC aresonant condition exists, and the effective mechanical impedance, Z,,,,is equal to the mechanical resistance, R the reactive impedancecomponents wM and 1/ wC cancelling each other out. Under such a resonantcondition, velocity of vibration, u, is at a maximum, power factor isunity, and energy is most efficiently delivered to a load to which theresonant system may be coupled.

Just as in electrical circuitry, maximum acoustical energy can betransferred where a good impedance match exists. i.e., where the twoelements between which the energy transfer occurs have like impedances.This fact becomes significant in the device and method of this invention in the transfer of energy from the driving end of the mandrel andthe casing or piling to the earthen formation in effecting thepre-punching and final driving operations respectively. Thus, in view ofthe high resistive impedance characteristics of earthen formations it isdesirable that the driving end of the mandrel and casing or pilingexhibit corresponding high impedance characteristics to assure maximumtransfer of energy in fluidizing the formation.

It is to be noted that in the device of this invention the mass andcompliance for forming the resonantly vibrating system are furnished bythe structural members of such system themselves such that the earthenformation is not incorporated in such system. The earth under suchconditions acts as a friction load which provides no significantreactive components. This results in a random vibration of the earthenparticles, rather than a lumped coherent vibration, with a considerablerelative motion between the separate grains. The net result is a highdegree of fiuidization of the earthen structure facilitating thepenetration of the driven member and the eventual compaction of suchstructure around such member when the sonic energization is terminated.

It is also important to note the significance of the attainment of highacoustical Q in the casing member being driven, to increase theefiiciency of the vibration thereof and to provide a maximum amount ofenergy for the driving operation. As for an equivalent electricalcircuit, the Q of an acoustically vibrating circuit is defined as thesharpness of resonance thereof and is indicative of the ratio of theenergy stored in each vibration cycle to the energy used in each suchcycle. Q is mathematically equated to the ratio between wM and wR Thus,the effective Q of the vibrating circuit can be maximized to make forhighly efiicient, high amplitude vibration by minimizing the effect offriction in the circuit and/or maximizing the effect of mass in suchcircuit.

In considering the significance of the parameters described inconnection with Equation 1, it should be kept in mind that the totaleffective resistance, mass, and compliance in the acoustically vibratingcircuit are represented in the equation and that these parameters may bedistributed throughout the system rather than being lumped in any onecomponent or portion thereof.

Referring now to FIGS 1-4. a first embodiment of the device of theinvention is illustrated as being utilized in performing the pre-boreoperation of the method of the invention.

Gasoline engine 11 is mounted on platform 12 by means of bolts 14. Gearbox 13 is supported on platform 12 by means of bolts 17. Platform 12 isresiliently mounted on support member 16 by means of spring mountingassemblies 18. Mounting asemblies '18 are attached to crossbars 20 whichare fixedly attached to platform 12 by welding. Mounting assemblies 18include springs 21 which are held within retainer members 22, the topone of each of these retainer members being attached to a respective oneof crossbars 20, the bottom one of each of such retainer members beingattachcd to support member 16. The ends of springs 21 are effectivelyretained in retainer members 22 so that when the entire assembly islifted upwardly by means of cables 30, the springs will, under tension,support such assembly.

Contained within gear case 13 is a gear train including gears 25-28,each of these gears being mounted on an associated shaft 31-34respectively, for rotation on bearings contained within casing 13.Engine 11 rotatably drives shaft 31 and gear 25 in the directionindicated by the.

arrow in FIG. 2. With such rotation of gear 25, the other gears 26-23are rotatably driven in the directions indicated by the associatedarrows in FIG. 2.

Fixedly mounted on support member 16 by means of bolts 40, is rotorhousing 42. Mounted for rotation within housing 42 are eccentric rotors45 and 46 which are attached to shafts 47 and 48 respectively, theseshafts be ing rotatably supported on the housing. Shafts 33 and 34 arecoupled to shafts 48 and 47 respectively by means of associated U-joints50 and 51 (see FIG. 3). Thus, rotors 45 and 46 are rotatably driven inopposite directions as indicated by the arrows in FIG. 4.

Referring now to FIG. 1, fixedly attached to support member 16 ishydraulic clamping mechanism 55. Hydraulic clamping mechanism 55includes a piston member 56 which is slidably supported in a cylindermember 57. When hydraulic pressure is applied to piston 56 throughhydraulic control line 60, piston 56 is driven into tight clampingengagement with the top portion 61a of mandrel member 61. Mandrel member61 is thus tightly retained between the jaws formed by serrated wall 63and the serrated end portion 56:! of piston 56. When the hydraulicpressure is released, piston 56 is urged away from the mandrel wall byspring 65, thus releasing the mandrel.

The device of the invention is utilized to bore a hole in earthenformation 66 in the following manner: With mandrel 61 being tightly heldto support member 16 by means of hydraulic clamp 55, the entire assemblyis lifted into position for boring by suitable means, such as a craneassembly which is connected to cables 30. With mandrel 61 verticallypositioned with its end portion 61b abutting against the earthenformation to be penetrated, engine 11 is turned on so as to causerotation of eccentrically weighted rotor members 45 and 46. It is to benoted that in the event that a hollow mandrel is used, the end portion61b thereof should usually be capped to prevent the entry ofunconsolidated earthen material therein.

Rotors 45 and 46 are position phased as indicated in FIG. 4 and whenrotated in opposite directions produce vibrational forces that areadditive longitudinally and which effectively cancel each other outinsofar as transverse vibration is concerned. Mandrel 61 is thuslongitudinally vibrated at a frequency determined by the speed ofrotation of rotors 45 and 46. This rotation speed is adjusted so as toproduce resonant vibration of mandrel 61 with standing waves asindicated by graph lines 68 being set up therealong. As indicated bygraph lines 68, maximum vibrational activity is provided at the boringend of mandrel 61 where it is most needed to accomplish the boringoperation. It is further to be noted that once the properly dimensionedorbiting mass oscillator has been set to cause resonant vibration of themandrel, that it tends to automatically adjust its rotation frequencysuch as to maintain such resonance with changes in the impedance of theresonantly vibrating system.

Mandrel 61 is preferably fabricated of a material such as steel havingrelatively high Q characteristics to make for a resonant system havingoptimum efficiency.

When the desired penetration depth has been achieved, the mandrel 61 islifted out of the bored hole by means of cables 30, sonic excitationthereof being continued as necessary to facilitate such removal.

During this first operation, the earthen particles are fluidized andcompacted so that they in effect stand back from the mandrel permittingrelatively easy penetration. In view of the fact that the resonantvibration system is contained fully within the mandrel and theassociated components, the earthen material being penetrated tends toact as a resistive load with the particles being caused to vibraterandomly rather than as a unitary mass. It is believed that each of theindividual irregular grains when energized by the sonic energy in thisfashion separately vibrates in a random path with a relatively fixedradius of vibration which changes in direction but remains fixed inmagnitude. Such random vibration effectively separates the irregularparticles so that they do not adhere to each other and are thus kept ina highly fluid condition. This high degree of fluidity not only greatlyeases the penetration of the mandrel member but also conditions the soilsurrounding the pre-bore so that highly effective lodgment of the casingor pile member subsequently driven therein is possible.

With certain soil conditions it has been found to be preferable to makethe pre-bore smaller in diameter than the casing member to he installed.Such a smaller diameter pre-bore is generally preferred where the soilhas a relatively low consolidation such as in the case of soft loam. Onthe other hand, a pre-bore having a larger diameter than that of themember to be installed may be preferable with other types of soilconditions.

Referring now to FIGS. 58, a second embodiment of the device of theinvention is shown as being utilized to drive a casing or pile memberinto the pre-bore. This embodiment is similar to the first embodimentdescribed except for the addition of a resonant spoke member whichprovides an elastically vibrating system independent of the casing orpile member to be driven. The use of such a resonant spoke member hastwo advantages. First, it

enables the attainment of resonance where a relatively short member tobe driven is involved; and secondly, it obviates the necessity forresonantly vibrating the driven member so as to avoid subjecting suchmember to overly large vibrational forces, this second factor beingparticularly significant where relatively frangible casing or pilemembers are being installed.

Spoke member 70 comprises a ring portion 74 having a plurality of radialspokes 71 extending therefrom. The spoke member is formed in twosections so that it can readily be attached to and detached from supportmember 16. This enables the utilization of the sonic driving mechanismalternatively either with a resonantly vibrating driven member or theresonant spoke member. The spoke member has a groove 72 formed in thering portion 74 thereof, such grooved portion fitting over the edge ofsupport portion 16. Spoke member 70 is removably attached to supportmember 16 by means of bolts 73.

The dimensions of spoke member 70 are such that the sonic vibrationalenergy generated by the orbiting mass oscillator contained withinhousing 42 will cause resonant vibration of the system including suchspoke member and support member 16. Engine 11 and its associated driveassembly is, as in the case of the first embodiment, isolated fromplatform 16 by means of spring isolator members 18.

Cit

The casing or pile member 78 to be installed is tightly held to supportmember 16 by means of hydraulic clamp assembly 55. The member 78 to beinstalled does not form an elastic part of the resonantly vibratingsystem and rather acts as a lumped constant inductive load thereon. Thevibrational energy coupled to member 78 is coupled therefrom to earthenformation 66. Casing 78 is thus driven into the pre-bore 89 previouslyformed by the mandrel. It is to be noted that as member 78 is sonicallydriven, that the soil 66 is compacted away from the wall of such memberwith the individual particles thereof being maintained in a highly fluidstate by virtue of the random vibration instituted therein. With theearth particles standing back in this fashion, member 78 can easilypenetrate into prebore 80. When the sonic excitation is halted, thefluidized soil particles fall tightly against the casing walls in ahighly compacted state which results in firm lodgment of such casingmember in its finally installed position.

It is to be noted that while the utilization of spoke member 70 isdescribed in conjunction with the driving of the member to be installed,it could also be utilized to equal advantage in conjunction with themandrel in making the pre-bore should the situation so require.

In practicing the method of the invention, the mandrel 61 is firstutilized as described in connection with FIGS. 1-4 to make a pre-borefor receiving the casing or pile member to be installed. In such firstoperation, the soil 66 in which the pre bore is formed is fluidized andcompacted away from the mandrel, with the individual grains of the soilvibrating in random fashion relative to each other. The soil not beingpart of the resonantly vibrating system does not vibrate as a unitarymass, and thus the individual particles are highly fluidized. When themandrel 61 has penetrated to the desired depth, it is withdrawn from theearth, leaving the pre-bore 80 with the soil surrounding same in optimumcondition for the second step involving the installation of member 78.

When mandrel 61 has been removed from the pre-bore it is detached fromsupport member 16 by deactuation of hydraulic clamp member 55. Themember 78 to be installed is then joined to support member 16 by meansof the hydraulic clamp, and set into position over the prehore 80 bymeans of a suitable crane mechanism (not shown) connected to platform 12by means of cables 30. With member 78 in position, sonic energy isapplied thereto from the resonantly vibrating system including sup ortmember 16 and spoke member 70, which is resonantly excited by theorbiting mass oscillator.

The vibrational energy passes through member 78 to the soil 66 causingit to stand back away from member 78 thus permitting penetration of suchmember into the prebore. The second activation of the soil again causesrandom vibration and further compaction thereof, further fluidizing thesoil structure. When member 78 finally reaches the bottom of thepre-bore, or a predetermined distance beyond, resonant sonic excitationthereof is discontinued. When this occurs, the earth particles settletightly against the Wall of casing member 78 in a highly compactedcondition, firmly gripping such member and holding it in firm lodgmentin the earthen formation.

The method and device of this invention thus provides means forfacilitating the installation of easing, pile members or the like inear-then formations, wherein a superior installation of such member isachieved. By virtue of the pre-conditioning of the soil achieved in thepre-bore operation and the following excitation of the earthen formationin a manner which provides optimum fluidization and compaction thereof,the member to be installed is firmly lodged in and supported by thepenetrated soil structure. Further, means are provided in the form of aresonant spoke member for achieving resonant vibration of the over-alldrive system without resonantly exciting the member being driven, thusminimizing the chances of damaging relatively frangible such membersduring the driving operation and enabling the driving of relatively 7short members incapable of achieving self-resonance at the vibrationaldrive frequencies.

While the method and device of the invention have been described andillustrated in detail it is to be clearly understood that this isintended by way of illustration and example only and is not to be takenby way of limitation, the spirit and scope of this invention beinglimited only by the terms of the following claims.

I claim:

1. A method for installing an elongated member in an earthen formationcomprising the steps of forming a pre-bore in said earthen formation andiiuidizing and compacting the earthen particles surrounding saidpre-bore by sonically vibrating a mandrel member to cause such member tobore into said formation,

when said pre-bore condition has been achieved, removing said mandreltherefrom and placing said member to be installed in said pre-bore,

sonically vibrating said member to be installed so as to cause furtherfluidization and compaction of the soil in said pre-bore and to causesaid member to be driven therein, and

when said member to be driven has penetrated into said pre-bore to thedesired depth, discontinuing the sonic energization thereof whereby theearthen particles surrounding said member fall tightly against saidmember in tight gripping relationship there-with.

2. The method as recited in claim 1 wherein said mandrel member isresonantly vibrated as part of a resonant vibration system independentof said earthen formation.

3. The method as recited in claim 1 wherein a resonant elastic member isconnected to said member to be installed during the sonic vibrationtheerof, said elastic member forming part of a resonant vibration systemcoupled to said member to be installed, whereby said member to beinstalled acts as a vibratory load on said resonant system.

4. The method as recited in claim 1 wherein said mandrel member and saidmember to be installed are vibrated by means of an orbiting massoscillator.

5. The method as recited in claim 1 wherein the prebore is made to havea slightly smaller diameter than that of said member to be installed.

References Cited UNITED STATES PATENTS 2,229,912 1/1941 Baily 175-55 X3,023,820 3/1962 EDesvaux et al 175-55 3,049,185 8/1962 Herbold l75-l93,076,513 2/1963 Heaphy 175-55 X 3,187,513 6/1965 Guild 175-19 X3,309,877 3/1967 Degen l7519 CHARLES E. OCONNELL, Primary Examiner.

R. E. FAVREAU, Assistant Examiner.

1. A METHOD FOR INSTALLING AN ELONGATED MEMBER IN AN EARTHERN FORMATIONCOMPRISING THE STEPS OF FORMING A PRE-BORE IN SAID EARTHEN FORMATION ANDFLUIDIZING AND COMPACTING THE EARTHEN PARTICLES SURROUNDING SAIDPRE-BORE BY SONICALLY VIBRATING A MANDREL MEMBER TO CAUSE SUCH MEMBER TOBORE INTO SAID FORMATION, WHEN SAID PRE-BORE CONDITION HAS BEENACHIEVED, REMOVING SAID MANDREL THEREFROM AND PLACING SAID MEMBER TO BEINSTALLED IN SAID PRE-BORE, SONICALLY VIBRATING SAID MEMBER TO BEINSTALLED SO AS TO CAUSE FURTHER FLUIDIZATION AND COMPACTION OF THE SOILIN SAID PRE-BORE AND TO CAUSE SAID MEMBER TO BE DRIVEN THEREIN, AND WHENSAID MEMBER TO BE DRIVEN HAS PENETRATED INTO SAID PRE-BORE TO THEDESIRED DEPTH, DISCONTINUING THE SONIC ENERGIZATION THEREOF WHEREBY THEEARTHEN PARTICLES SURROUNDING SAID MEMBER FALL TIGHTLY AGAINST SAIDMEMBER IN TIGHT GRIPPING RELATIONSHIP THEREWITH.